Tank-truck kmergency-valve system and controller



Apr 1931. J. H; MCEACHERN TANK TRUCK EMERGENCY VALVE SYSTEM AND CONTROLLER s sheets sheet 1 Filed Nov. 4, 1924 an faelizi n/ attoz uuf April 21, 1931.

J. H. M EACHERN TANK TRUCK EMERGENCY VALVE SYSTEM AND CONTROLLER Filed Nov. 4, 1924 3 Sheets-Sheet 2 April 21, 1931, J. H. MCEACHERN TANK TRUCK EMERGENCY VALVE SYSTEM AND CONTROLLER 3 Sheets-Sheet 3 Filed Nov. 4, 1924 .m t n M W M v w w w J 4 mm 0 m T J w o: L o o z l N w 0 O C FL Q; Q; o, 0 /1\ a f t: 2 Mm 3 3 6 Patented Apr. 21, .1931

UNITED STATES JOSEPH H. MUEACHERN, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOB, BY ZMESEISTIE'r AB- PATENT OFFICE SIGNMENTS, TO STANDARD OIL COMPANY OF CALIFORNIA, OF SAN FRANCISCO, CALIFORNIA, A. CORPORATION OF DEL-AWARE 'rlmx-raucx I EMERGENCY-VALVE SYSTEM AND CONTROLLER Application filed November 4, 1924., Serial No. 747,784. 4

In my application, Serial Number 690,287,

filed February 2nd, 1924, I have described a tion. to which the inventionhas pressure controlled emergency valve system for tank trucks. The specific embodiment of the invention described in the said application is pneumatically controlled although it is not intended to restrict the generic character of the invention to such pneumatic control. One of the present objects is to disclose a pressure system of the character referred to which is hydraulically controlled.

A further object of the present invention is to provide in the system means for releasing the pressure in the system upon an overrise in temperature to thereby close the emergency valves in the event of fire.

A further object of this invention is the provision of an improved controller or operating pump adapted for employment in the aforesaid system as well as for any of the various uses to which this character of controller or operating pump may be put. Among the advantages sought for such controller or operatingpump are the elimination of all valves, and the provision of an elasticity permitting use with an incompressible fluid within predetermined Other advantages and features of the invention will appear from, the followin description of the application of one em diment of all features of the invention to a tank truck, it being understood that the application shown is by way of example, and that the invention is not specifically limited thereto.

In the drawings:

Figure 1 shows a tank truck pzrtly in see- Fig. 2 is a fragmentary view-showing the connections below the tank, illustrated in Fig. 4 is a vertical section through the con-v troller or operating pump taken on the line indicated at 4-4 Fig. 8.

on applied.

Fig. 5 is a rear elevation of'the controller or operating pump with parts broken away.

Fig. 6 is a section 0 the controller or operating pump taken on a line indicated by 6-6 in Fig. 4.

Referring to the drawings: The tank truck illustrated in Figure 1 carries a tank 2 of the type having a plurality of fluid compartments 3. An emergency internal valve 4 is mounted within each compartment by means of a pipe flange '5. The emergency valves 4 correspond in construction to the emergency internal valves described in my said application Serial Number 690,287, and no further re ference will be here made to the construction of these valves other than that they are provided with tension means for normally maintaining the valve closed and are opened by pressure transmitted through a pressure line 6.. A discharge pipe 7, customarily equipped with a faucet 8 is provided for each compartment of the tank and is connected at the pipe flange 5 secured at the under side of the compartment from which the pipe leads.

A valve 6 provided for priming the line 6 and this valve 6 also serves as one means for venting the said line 6; the valve is illustrated at the forward end of the line 6 but may be placed at any convenient point along its length.

The pressure line 6 is provided with a plurality of crosses 9 corresponding in numher to the number of the emergency valves 4 in the tank 2. The emergency valves 4 are respectively connected to the pressure line 6 through lines 10 leading from the crosses 9. The fusible plug 11 is inserted in each cross 9. In the event of fire the fusible plug 11 will respond to the raise in temperature and vent the pressure line 6, closing the emergency valves 4. This assures that the-contents of the tank will not drain therefrom in the event the fire prevents the operation of the 4 to be 0 ned by applying a pressure to the valve 4 t rough the pressure line 6. A suitable oil willpreferably be employed as a hydraulic medium in the pressure system.

The controller or operating pum 12 is actuated by an operating arm 14. 5 may be seen particularly in Fig. 3 of the drawings, the controller or operating pump 12 is preferably provided with a latch or tripping device 15, which serves to engage and secure the operating handle 14 when the handle is brought to its rearward or pressure applying position. The latch 15 1s pivoted on a pin 16 mounted in the boss 17 and is actuated y a tension spring 18. A bracket 19 serves to position the latch 15 so that it intercepts the operating handle 14. An extension 15 on the latch 15 is so positioned that it may serve as a means of rocking the latch 15 and releasing the operating arm 14. A spring 20 serves to return the operating arm 14 to orward or pressure releasing position. striker 21 may be mounted on the swinging end of the pivoted bucket box door 22 to trip the latch 15 to release the operating arm 14 when the door 22 is closed. The. latch and tripping arrangement above described may be employed if desired but is not indispensable.

The construction of the controller or operating pump 12 is novel and although particularly adapted for employment in an emergency valve pressure control system its use is not limited thereto. The construction of this controller or operating pump 12 is shown in detail cross section in Fig. 4 of the drawings. The controller'or operating pump 12 has a main body forming a c linder 23 and an oil or fluid reservoir 24. The upper outer wall 25 of the main body of the controller or pump is preferably spaced from the cylinder 23 to provide a fluid assage 26 communicating with ports 27. E suitable piston is provided in the cylinder 23 by means of which the fluid from the reservoir or tank 24 may be supplied to and maintained under the required pressure to maintain the valves 4 open Preferably this piston is of such form and construction as to provide a means for compensating for any leakage of fluid and the automatic maintenance of sufficient pressure.

to maintain the valves 4 open. Preferably, therefore the piston is made in two parts 28,29. As shown these are in the form of cylmders with one end open. The open ends of the c linders being turned toward each other. hrough the end wall of the rear part 29 is inserted a suitable block 46 having a. central chamber. This block 46 is provided with a flange 46 which bears upon the end of the piston part 29. 31 represents a connecting rod which extends through the block 46 lengthwise of the piston and through the head of the piston part 28 This rod 31 is preferably provided with a head adapted to bear u on the surface about the opening throu i the block 46 into the chamber of the cylin or 23. A suitable spring 30 is interposed between the piston parts 28 29. 33 represents a cup leather of any ordinary or preferred construction mounted on the front face of the piston 28 and retained in position by means of the spring retainer 34 and Washer 35 and loading spring 36 maintained in position by a nut 32 on the end of the rod 31.

A yoke 37 is connected at a pin 38 to the block 46 and at its opposite end at a pin 39 to a lever arm 40. The lever arm 40 is rigidly connected with the shaft 41 by means of a pinch collar 42. The operating arm 14 .is also rigidly secured to the shaft 41 by a pinch collar 43. A packing gland 44 prevents the leakage of fluid at the point where the shaft 41 projects from the housing. The motion imparted to the rear piston 29 by the oper- A ating arm 14is restricted by the lever arm 40 striking a stop 45 in one direction and in the reverse direction when the operating arm 14 strikes the latch 15. The spring 30 is 'normally held in compression between the front and rear piston arts 28, 29 by the rod 31. When the arm 14 as been operated to actuate the piston inward, the ressure of fluid in the system is normally su cient to sto the inward motion of the front end 28 o the pnton and to cause the rear end 29 of the piston to further compress the spring 30 thus providing for the maintenance of pressure upon the system. The front head 47 and rear head 48 are suitably secured to the controller or pump body so as to maintain the whole fluid tight. When the lever arm 40 is against the stop 45 the cup leather 33 is behind the ports 27 and fluid communication exists between the cylinder 23 through the ports 27 and fluid passage 26 to the fluid reservoir 24. vent 49 assures that only atmospheric pressure can exist within the fluid reservoir 24. The operating pump 12, as illustrated in 4 of the drawings, is in the position in Wl'llC the emergency shut-off valves 4 are closed since the cup leather 33 is behind the ports 27, and the pressure line 6 and emergency valves 4 contain fluid subject only to atmospheric pressure plus the small static head necessary to keep the system full of fluid. The springs within the emergency shut-off valves, described in detail in application Serial Number 690,287, are made sufliciently strong to overcome the static head and seat and maintain the emergency shut-o valves normally firmly seated. To raise the emergency shut-0E valves 4, the operating handle 14 is pulled back and engaged in the latch 15, forcing the part 29 forward a given vdistance. The forward movement of this part 29 also causes a forward movement of the forward piston part 28 through the medium of the compression spring 30. The cup pressure within the cylinder 23 is established equal to the compressive force of the spring 30. On further movement of the part 29 the spring 30 is further compressed as the pres sure increases on the face of the piston 28. Thepredetermined pressure at which the compressionspring 30 is further compressed is sufficient to overcome the spring tension maintaining the emergency valves 4 normally closed, and allows the expansible bellows in such emergenc valves to be inflated to open the valves, without subjecting the emergency valves 4 to a hydraulic pressure suflicientl highto endanger or rupture the expansi le bellows in such valves. The compression spring 30 serves the further purpose of providing for maintaining the emergency valves in a fully open position against a certain amount of fluid leakage as the front piston 28 with the cup leather 33 will tend to move forward, within the ran e of the additional or stored compression 0 the spring 30, to overcome an fluid leakage by additional displacement o fluid from the cylinder 23.

To releasethe hydraulic pressure in the line 6 and thus permitthe emergency valves 4 to assume their normal closed position, the operating handle 14 is disengaged from the latch 15, either manually or by contact with the striker 21, and the pressure exerted by uid in the pressure line system t us forces the iston- 28 in the controller or pump 12, aided y the tension spring 20 on the operating handle 14, back to the emergency valve open position shown in Fig. 4.

The construction of the controller or operating pump 12 is such that no valves are used in the system and the liability of valves to leakage is eliminated. The cup leather 33 with the loading spring 36 moving in the cylinder 23 rovides a fluid tight device. Throu h t e emplo ent of the above describe piston assem ly an elastic mechanical medium is provided, although the hydraulic medium is a practically incompressible fluid, thus allowin the o crating handle 14 to be given a fixe and efinite motion for openin the emergency shut-01f valves and provi ing for the limiting to a predetermined value the-fluid pressure that may be exerted upon the emergency shut-ofi valves and further providing an elastic take up to maintain that pressure against a certain amount of'fluid leakage. v p

The above described arrangement provides an emergency shut-off valve'system for tanks,

fiarticularly useful for tankjtrucks and the ke, which is positive in operation and conthe springs in the emergency valves 4 u on' the ing discharged the fuse plugs 11 will vent the pressure line immediately closing the emergency shut-off valves, although the fire prevents movement of the operating arm 14. The bucket box door on the tank truck is always closed by the driver prior to starting the truck since, if he does not close this door, the buckets and funnels carried within the box will fall out. It is assured that the emergency shut-.oif valves will be closed al- .though the driver forgets to'move the operating handle 14 because when the driver closes the bucket box door the striker 21 will release the latch 15 and the operating arm 14 will automatically move to itspressure releasing position.

The invention is not specifically limited to the particular arrangement and construction above described, but is of the scope set forth in the appended claims.

I claim:

1. The combination with a. tank truck having a plurality of pressure actuated emergency shut-off valve units mounted in the tank, an always open pressure line Commof a fire occurring while the tank truck is bei cating with said valve units, and a pump adapted to create a fluid pressure in said line to open said valve units, the fluid displacement capacity. of the pump being greater than the combined fluid capacity necessary to open said valve units, and means to maintain fluid pressure in said pump to hold said valve 7 units open. 7

2. The combination with a tank truck, of

emergency shut-0E valve units mounted 7 within the tank, the valve units having springs to normally maintain the valves closed and expansible bellows for opening the valves, a pressure system for opening the valves, and a hydraulic control for the pressure system, said control having a two part piston and a compression spring interposed between,- such parts where y in operation the unti a predetermined pressure within the cylinder is established whereupon the forward part. of the piston will stop and the sprin be further compressed, the predetermine pressure at which the spring is further compressed being suflicient to overcome the s rings within the emergenclyevalve units there a lowing the bellows to inflated to open t e valves without endangering the bellows.

iston will be forced forward as a unit no I - 65 venient and practical in installation. In case and said reservoir to displace liquid from the cylinder into said hydraulic connection to open, said valves.

4. In combination with a tank truck, normally closed emergency valves in the tank, a non-circulating hydraulic system for opening the valves, a pump for creating a hydraulic pressure in the system, and a fuse member in said hydraulic system for venting the system in case of fire.

5. In combination a tank truck, normally closed pressure actuated emergency valves mounted in the tank, a non-circulating hydraulic system for opening the valves, a pump for creating hydraulic pressure in the system of the pressure actuated emergency valves and a fuse member in the hydraulic system for venting the system in case of fire to dispense the hydraulic pressure and permit the emergency valves to close.

6. In combination with a tank truck, normally closed hydraulically operated emergency valves, means for normally urgin said valves to closed position, a non-circu ating hydraulic system for opening the valves, and a reversible pump for creating a surging hydraulic pressure in said system alternating with the reversing of said pump to produce in said system a limited hydraulic pressure sufficient to open said valves but insufiicient to rupture the hydraulically operated emergency valves and to alternately open and close said emergency valves as the pump is reversed to alternately create and disperse said limited hydraulic pressure.

Signed at San Francisco, Calif., this 22nd day of October 1924.

JosEPH H. MQEACHERN. 

